Okay, maybe you can get a better idea by actually seeing it. Here is a link for the software. Of the four listed, MUSHClient is the best, though, as it says, it is more complex. Just don't play with anything until you have been MUSHing for awhile and know what it does.
http://www.geocities.com/dan_rustine/mushdownload.html)
Anyway, once you get it started up, click on the new doc icon in the upper left hand corner. Here is the connection information:
Star Wars: A New Threat (One of my personal favs)
IP address:starwars.pennmush.org
Port: 9999
There are many SW MUSHes out there, but this is one of the most active. Anyway, everything is pretty much explained. Just remember to carefully read the text and do what it says. If you have any problems, feel free to contact me here or via my listed e-mail. Also, when you register yourself [reg (name) (e-mail)], remember that whatever you choose for you're name is your characters name. Feel free to look for me, Caleb Babcox.